javascript - How to set the default value of dropdown-menu base on URL param? -

this question has answer here:

• using parameter of url in javascript [duplicate] 11 answers

i have url url param userid

http://localhost:8080/assignment?userid=s-00589

i have dropdown-menu

i can access url param , userid.

now i'm wondering how use userid set default dropdown-menu one.the 1 value="s-00589"

any helps / suggestions appreciated.

should literally simple as:

$('#rn-dd').val(userid_from_url);